Key Terms: Self-management, genetic disorder, chronic disease, children, grounded theory, genetic counseling, Marfan Syndrome. This exploratory, descriptive, grounded theory investigation will answer the question: how do parents transfer and children take on responsibility for managing a chronic genetic disorder? For the purpose of this project self-management is defined as the individual's self-directed participation in life-long self-surveillance and self-care skills that promote health. Theoretical assumptions from the social theory of Symbolic Interactionism direct the methods. The specific aims are: (1) to describe how children take on and parents transfer to the child the responsibility for managing a chronic illness; (2) to construct a conceptual model of the psychosocial process of transition to self-management from the collective experiences of young patients, parents, and health care providers; and (3) to propose counseling guidelines for nurses, genetic counselors, and physicians who care for families in which a child has a chronic genetic illness. 40 parents, 40 children with Marfan syndrome (MFS), and 15 healthcare providers will be recruited from a regional genetics clinic and the National Marfan Foundation and interviewed twice. Individuals with MFS are selected because this prototypical genetic disorder is diagnosed in childhood and causes complex, multi-organ system problems that emerge over a life-time. The experiences of individuals with MFS mirror the health care needs of several groups of patients with chronic disease and other single gene disorders diagnosed in childhood. An interpretive content analysis of transcribed audiotapes will result in a theoretical model that illustrates the psychological and social variables and the social processes that are fundamental to a child's successful transition to self-management. This study will have practical implications for the preparation of nurses, genetic counselors, and physicians who care for families with chronic illness diagnosed in childhood. It will contribute a theoretical model that has relevance and is transferable to other chronic illnesses. Components of the model may be used by public health officials to evaluate transition services at health clinics. The study will generate testable hypotheses for future research and produce recommendations for counseling patients and parents. The study will provide information immediately usable by health care providers to make evidence based clinical judgments.